Post
Topic
Board Mining support
Re: S17+ Chip repair questions
by
moftkhor
on 20/09/2021, 19:18:43 UTC
Hello

I have a bunch of S17+ hashboards piled up for repair and I've been keeping busy with figuring out as much as I can. Sadly for technicians that like to do everything themselves like me, there is not much detailed info out there on this issue. Most info I found were in Russian or some other foreign language I couldn't understand.

So to repair my hashboards I'm left with a few questions I hope you guys can help me out.
I'm an electrician myself and I have quite some tools in my workshop so that's not really an issue.

1) Until now I used the black bitmain glue to stick the heatsinks back on, but I found that the chips with the glue got hotter. Now I would like to try using soldering
    tin to fix the heatsinks back on the chips. Can anyone tell me exactly what tin I need to buy?

2) How do you guys figure out which chip exactly is malfunctioning? I got a voltmeter, I got the Zeus test fixture (but in an earlier topic a few people told me that
    test fixture is practically useless as it keeps turning off the hashboard). Is it possible to measure the malfunctioning chip by resistance? If so, does someone
    know what resistance in Ohm every measuring point needs to be approximately? Or is the only way to measure by voltage and powering on the hashboard?

3) I also see a lot of Temperature sensor errors. But sadly can't find a lot of info about how to measure it. How can I measure the temperature sensors?

4) I often use my Supersonic bath to clean the hashboards, as I find a lot of times the chip legs rusted and bridged together, this way helps a lot to get
    them nice and clean, but the heatsinks usually fall off when I do that. Does anyone know if they sell a heatsink template for hashboards so we could glue/solder
    the heatsinks much faster on the hashboard? Been looking all over google, but can't find anything. I'm thinking of buying an aluminum 3d printer just to make
    that now...


Thank you guys for responding!




Hello,

1. You need low solder paste. for example Bismuthum+Sn (Sn42Bi58).
2. You need very,very,very good bench multimeter, best to use is the 4-wire method or you can buy somewhere miliohm meter. I use keithley 2000 .
you can measure resistance between chip 1,8Volts, is it best method for found cold solders for me, but you need very good multimeter/miliohm meter.
3. You can use I2C analyzer, or change sensor and asic chip which is connected to the sensor.
4. Be careful with supersonic bath, tin is very fragile because bitmain use low solder paste. You can make more cold connections between chip and board.
I use PCB cleaner and little antistatic brush

M.


I'm sorry I just noticed there were comments on my topic.
Thank you for the expanded explanation.

How does the I2C analyzer work exactly? What does it do?